The invention relates to a color scale palette and, more particularly, one for the identification and selection of a dental material.
As used herein, the term "dental material" is to be understood to refer to dental filling materials, prosphetic detal materials for the preparation of dental plates, manufactured teeth and tooth parts, and the like.
German patent publication No. G 1,714,429 discloses a color scale palette in the form of a plastic stick arranged to hold removable color rods in a row as color samples. For this, the stick has recesses which removably accommodate the color rods. For use in selecting the color of a dental material, therefore, several color rods which appear from general inspection to be most suitable could be identified first, and these color rods then removed from the stick for more-exacting selection. For example, in selecting the color for a manufactured tooth to be inserted in a person's mouth between other teeth, the color rods generally appearing most suitable in relation to the color or colors of the other teeth could be selected first, and these then removed from the stick for selecting the best one by juxtaposed comparison with the other teeth.
This procedure seems simple, but is, instead, complex for reasons relating both to the problems of color selection and to the color scale palette used for the selection. Color selection is difficult because the preception of color is variable and, even once perceived, the selection of the most suitable color is artistically esoteric. These problems are particularly acute in relation to dental materials.
The dental materials and the natural or other mouth structures with which the dental materials are to be used are often translucent and, in situ, moist. The translucence and the gloss of the moisture affect the appearance of color. The color for dental materials is usually selected indoors where artificial light is used, but the color of the dental materials, once in place in a person's mouth, must also appear appropriate when the person is out doors. The dental materials are also used in very close proximity to natural or other mouth structures so that correspondingly close precision in color selection is required. Shadows compound these problems because the intensity of the light and its angle in assessing the color affect the appearance of the color to be selected. Finally, at least natural mouth structures are not one color, but many, and vary widely from person to person, so that neither mere mechanical selection nor reference to standard pre-selected colors is a satisfactory substitute for individual artistic selection.
All these problems are compounded by the difficulty of satisfying each individual who is to receive the dental material not only with the color finally selected, but with the cost of making the selection and, of course, implementing it.
In relation to the color scale palette, these problems mean that the color scale items, the color rods of the above-referenced patent publication, must be shaded precisely and, hence, sufficiently large and numerous. They must not fall from their holder during initial selection, yet be removable for juxtaposed comparisons under both artificial and natural light and returnable to the palette easily to allow both accurate and efficient selection. Further, it would be desirable to have the color scale items (rods) coded as to color identification and/or dental material(s) for implementing the color selected and arranged to avoid shadows at least in the juxtaposed comparison.